Systems and methods are disclosed for implementing an event based retention schedule for a read only file. When a regular file is to be converted to an event based retention read only file, an “event-retain” property may be enabled on the file allowing the feature to be implemented. Then, that file may have its permissions changed to read only. This will allow the file to be changed to a read only file without using a default retention time. Then, once the event is triggered, the retention time may be set so the file can be scheduled for automatic deletion.